// 3个求绝对值函数的使用

#include <iostream>
#include <stdlib.h>
#include <math.h>
using namespace std;

int main() {
    double f = -7.345f;
    int i = -3;
    long l = -44000L;

    cout << "正数值分别是: "
        << fabs(f) << ", "
        << abs(i) << ", "
        << labs(l) << "\n";

    cout << "标准库已经做了重载: " << abs(f) << "\n";
}